backup&recovery.enhancements.in.oracle10g-presentation.pdf

7/25/2019 Backup&Recovery.Enhancements.in.Oracle10g-Presentation.pdf

1/100

Backup & RecoveryEnhancements in Oracle

10g

Radoslav Rusinov

TechnoLogica Ltd.


2/100

2 of 100

Availability is the mostimportant characteristic of thebusiness data


3/100

3 of 100

Types of Failures and Oracles Solutions Human Errors

Export, Data Pump, Log Miner, TSPITR

Flashback Features Block Corruptions

RMAN

Media Failures RMAN Computer and Hardware Failures

RAC, Data Guard, Replication, Streams

Disaster Data Guard, Replication, Streams


4/100

4 of 100

Target Audience

Oracle DBAs ProductionEnvironments

Oracle DBAs Development

Environments Oracle Developers


5/100

5 of 100

Test Environment

Used Test Environment: Oracle Database Version: 10.2.0.2

Operating System: Windows XP SP2 Database Log Mode: ARCHIVELOG

Assertions in this presentation are in

result of tests performed on the aboveenvironment

Ensure that every feature works in the

expected way in your specificenvironment


6/100

6 of 100

Agenda

Flash Recovery Area Flashback Technology Enhancements

Space Pressure & Database Hangs

Physical Backup & RecoveryEnhancements

Conclusion


7/100

7 of 100

Automatic Disk-Based Backup & Recovery

with Flash Recovery Area

95% of the recovery operations need nomore than 3 days-old backups

What is Flash Recovery Area?

Unified disk storage location

Default location for disk-based backup files

Defines the max available space for disk-based backup files

Can use file system or ASM disk group


8/100

8 of 100

Flash Recovery Area (FRA)

Automatically names the files by using OMF

Has its own directory structure- ..\flash_recovery_area\ORCL102\

ARCHIVELOG AUTOBACKUP BACKUPSET CONTROLFILE

DATAFILE FLASHBACK ONLINELOG


9/100

9 of 100


FRA is not a place for the data files

Data files reside in the Database Area

FRA must be located on a different

physical storage than Database Area Configured with two parameters:

DB_RECOVERY_FILE_DEST- destination

DB_RECOVERY_FILE_DEST_SIZE max size


10/100

10 of 100


You can create your own additional

directories and files in FRA To configure retention policy:RMAN> CONFIGURE RETENTION POLICY TOREDUNDANCY | RECOVERY WINDOW OF

New RMAN commands to backup FRARMAN> BACKUP RECOVERY AREA only to SBT

device

RMAN> BACKUP RECOVERY FILES only to SBTdevice


11/100

11 of 100

Automated Space Management

Oracle does not delete the obsolete files. It

retain them until space pressure appears Behaves like a cache for backup files

Oracle issues alert when FRA is 85% full

Critical alert when FRA is 3% full

At 100% a message in the alert.log:

ORA-19815: WARNING: db_recovery_file_dest_size of bytes is 100.00% used


12/100

12 of 100

Space Pressure

Two file types reside in FRA

Permanent files: Multiplexed copies of control file

Multiplexed copies of online redo logs

Transient files: Archived redo logs

Datafile and controlfile copies

Controlfile autobackups Backup sets


13/100

13 of 100

Space Pressure

Archived logs in FRA that are in the recoverywindow and that are not yet backed up aretreated in a similar way as permanent files

Backup sets in FRA that are in the recoverywindow and are not yet available on tape aretreated in a similar way as permanent files

Space pressure over FRA causes automaticdeleting of transient files

Oracle never deletes permanent files


14/100

14 of 100

Space Pressure

Backup sets treated as permanent will notpermit creation of new backups and will not be

deleted Default Oracle installation uses FRA as

default and only one location for archived

logs: LOG_ARCHIVE_DEST_10 =USE_DB_RECOVERY_FILE_DEST

This along with the default value of:

LOG_ARCHIVE_MIN_SUCCEED_DEST=1 can makethe archivelog destination in FRA mandatoryand to cause space pressure


15/100

15 of 100

Space Pressure Recommendations

Set smaller and reasonable recovery window

Backup archived logs regularly Configure at least two archivelog destinations

Give more physical space to FRA

Configure the FRA size to be at most 90% ofthe real physical available space

For Disk-to-Disk-to-Tape strategies: backupbackupsets from FRA to tape regularly

For Disk-to-Tape strategies: perform databasebackups to tape regularly


16/100

16 of 100

Space Monitoring

V$RECOVERY_FILE_DEST

V$FLASH_RECOVERY_AREA_USAGE (10g R2):


17/100

17 of 100

Monitoring FRA Metrics with EM


18/100

18 of 100

Flash Recovery Area - Summary

Unified place for your disk-basedbackups

Automatically managed files

Simplified administration tasks

Faster Backup

Faster Restore


19/100

19 of 100

Agenda

Flash Recovery Area

Flashback TechnologyEnhancements

Space Pressure &Database Hangs

Physical Backup &RecoveryEnhancements

Conclusion

Flashback DATABASE

Flashback DROPFlashback TABLE

Flashback QUERY

Flashback VERSIONSQUERY

Flashback

TRANSACTIONQUERY


20/100

20 of 100

FLASHBACK DATABASE FasterPoint-In-Time Recovery


21/100

21 of 100

Flashback Database

Reverse the whole database to a pointin time

Faster recovery from user errors

Uses own logging mechanism Flashback Logs - stored in FRA

New process: Recovery Writer (RVWR) New SGA structure: Flashback Buffer


22/100

22 of 100

Incomplete Recovery vs. Flashback

Database


23/100

23 of 100

Advantages


24/100

24 of 100

Flashback Database

The availability of the archived logs within

the flashback recovery window is important The recovery depends on the size of

changes

Does not depend on the database size Prerequisites:

The database MUST be in ARCHIVELOG

FRA MUST be configured

The Flashback Logs can reside only in FRA


25/100

25 of 100

Configuration with EM


26/100

26 of 100

Manual Configuration SQL> STARTUP MOUNT EXCLUSIVE;

SQL> ALTER DATABASE FLASHBACK ON;

SQL> ALTER SYSTEM SETDB_FLASHBACK_RETENTION_TARGET = 1440SCOPE=BOTH;

Flashback can be stopped at tablespace level: SQL> ALTER TABLESPACE USERS FLASHBACKOFF;

Excluded datafiles must be offlined if the database

needs to be flashbacked and opened After flashbacking a media recovery for the offlined

datafiles must be performed


27/100

27 of 100

Flashback OFF for SYSTEM Tablespace

Oracle allows the flashback for logging forSYSTEM to be disabled

This leads to non-working flashback databasefeature

Dont exclude flashbacking for SYSTEMtablespace


28/100

28 of 100

Space Issues DB_FLASHBACK_RETENTION_TARGET

is a TARGET parameter It does not guarantee your recovery

window

Flashback logs are not archived and arereused

Flashback logs can cause spacepressure over FRA


29/100

29 of 100

Space Pressure

If FRA is Full -> Recovery Writer (RVWR)will start to reuse flashback logs

If FRA is Full -> transient files will bedeleted

Flashback logs are treated as transientfiles in FRA

They can be automatically deleted inresponse of space pressure


30/100

30 of 100

Space Pressure - Recommendations

Set Flashback retention target to areasonable value. No more than few days.

Do not configure flashback retentiontarget bigger than RMAN recovery

window Configure the FRA size to be at most 90%

of the real physical available space

To delete immediately all flashback logs:SQL> ALTER DATABASE FLASHBACK OFF;


31/100

31 of 100

Current Flashback Window

V$FLASHBACK_DATABASE_LOG


32/100

32 of 100

Restore Points (10g R2)

They are not exactly a feature of the

Flashback Database Can be used with FLASHBACK TABLE

They are a map between an SCN, TIMEand DATABASE INCARNATION

Rely on archived redo logs from around

the time of their creation


33/100

33 of 100

Restore Points (10g R2)

The most common cause for downtime

is change

Use them before performing of anysignificant change within the database:

Application upgrades

Batch jobs Starting of flashback database operations


34/100

34 of 100

Normal Restore Points (10g R2) SQL> CREATE RESTORE POINT

before_app_upgrade;

Can be created when FlashbackDatabase is OFF

Automatically deleted if: More than 2048 in count

Older thanCONTROL_FILE_RECORD_KEEP_TIME


35/100

35 of 100

Guaranteed Restore Points (10g R2)

SQL> CREATE RESTORE POINTbefore_app_upgrade GUARANTEE FLASHBACK

DATABASE;

Flashback Database can be OFF Using Flashback Logs

Could generate a lot of flashback logs


36/100

36 of 100

Guaranteed Restore Points (10g R2)

Not dropped automatically Must be explicitly dropped

Usable for short periods of time

Message in the alert.logafter their

creation

They can cause the Database to HANG


37/100

37 of 100

Using Flashback Database

SQL> STARUP MOUNT

SQL> FLASHBACK DATABASE TO TIMESTAMP

to_timestamp('10.04.200620:50','dd.mm.yyyy hh24:mi');

SQL> FLASHBACK DATABASE TO RESTORE

POINT before_app_upgrade;

SQL> ALTER DATABASE OPEN RESETLOGS;

(10g R2) Keeps flashback logs afterRESETLOGS

(10g R2) SQL> FLASHBACK DATABASE TO BEFORERESETLOGS;


38/100

38 of 100

Monitoring with EM

In Home Page

In RecoverySettings


39/100

39 of 100

Flashback Database - Summary

Very powerful for faster point-in-timerecovery

Generate much less flash redo than

online redo logs Can be used with restore points

Space consumer

I/O consumer

A d


40/100

40 of 100

Agenda

Flash Recovery Area

Flashback Technology

Enhancements Space Pressure &

Database Hangs


Conclusion

Flashback DATABASE

Flashback DROP

Flashback TABLE

Flashback QUERY


Flashback

TRANSACTIONQUERY


41/100

41 of 100

FLASHBACK DROP - Undo a Dropped

Table

Reverses the effect of a DROP TABLE

operation SQL> DROP TABLE my_table;

Uses logical container called RecycleBin

Table remains in the Recycle Bin

Can be queried


42/100

42 of 100

Flashback DROP

Using of Recycle Bin is ON by default

The objects in the Recycle Bin areincluded in backups

Can be disabled:

SQL> ALTER SESSION|SYSTEM SETRECYCLEBIN=OFF;

To remove a dropped table from the

Recycle bin: SQL> PURGE TABLE my_table;


43/100

43 of 100

Flashback DROP

To purge a tablespace:

SQL> PURGE TABLESPACE users;

To purge a user-specific objects: SQL> PURGE TABLESPACE users USER

app_user;

To purge all dropped objects in thedatabase: SQL> PURGE DBA_RECYCLEBIN;


44/100

44 of 100

Space Pressure

Objects in the Recycle Bin are not

counted as used space Oracle drops objects in the Recycle Bin

only in response of a space pressure

The recycle bin objects are deletedbefore performing automatic extending

of the datafile Be aware of user quotas


45/100

45 of 100

Flashback DROP

To restore a table from the Recycle bin:

SQL> FLASHBACK TABLE my_table TOBEFORE DROP;

Recover indexes

Does NOT recover constraints

Tables with defined security policies are

NOT kept in the Recycle Bin


46/100

46 of 100

FLASHBACK DROP - Summary

For fastest table recovery after DROP TABLE

Recovery success depends on the size of theunderlying tablespace

What is the difference:

1. SQL> DROP TABLE my_table;2. SQL> DROP TABLE my_table PURGE;

Most users are using the second statement

already

Agenda


47/100

47 of 100

Agenda

Flash Recovery Area



Database Hangs


Conclusion

Flashback DATABASE

Flashback DROP

Flashback TABLE

Flashback QUERY


FlashbackTRANSACTIONQUERY

R t d l t d t bl d t ith


48/100

48 of 100

Restore deleted table data with

FLASHBACK TABLE

Can recover table to a point in time inthe past

Uses information in the UNDO

tablespace Indexes, constraints and triggers are

restored automatically

Different feature than the FLASHBACKDROP


49/100

49 of 100

Flashback Table

Enable row movement for the table: SQL>ALTER TABLE my_table ENABLE ROW

MOVEMENT;

Recovers a table to a point in time: SQL> FLASHBACK TABLE my_table TO

TIMESTAMP to_timestamp('11.04.200620:50','dd.mm.yyyy hh24:mi');

Can be used with restore points:

SQL> FLASHBACK TABLE my_table TORESTORE POINT before_app_upgrade;


50/100

50 of 100

Flashback Table

Cannot be used after DDL operationsover the table

Use Flashback Database to recoverfrom:

SQL> TRUNCATE TABLE my_table; The recovery window depends on the

size of UNDO tablespace

Can be configured with:UNDO_RETENTIONparameter

S P


51/100

51 of 100

Space Pressure

It is a TARGET parameter

In 10g UNDO_RETENTIONis automaticallytuned

In 10g the recovery window can beguaranteed: SQL>ALTER TABLESPACE undotbs RETENTION

GUARANTEE;

This can cause the database to HANG

Agenda


52/100

52 of 100

Agenda

Flash Recovery Area



Database Hangs


Conclusion

Flashback DATABASE

Flashback DROP

Flashback TABLE

Flashback QUERY



FLASHBACK QUERY Recovery at Row


53/100

53 of 100

FLASHBACK QUERY Recovery at Row

Level

Allows a tables to be queried to the time

in the past

Available since Oracle9i

Uses UNDO tablespace Querying old state of my_table:

SQL> SELECT * FROM my_tableAS OF

TIMESTAMP TO_TIMESTAMP('11.04.200621:40', 'DD.MM.YYYY HH24:MI');

Fl hb k Q


54/100

54 of 100

Flashback Query

Configure recovery window withUNDO_RETENTIONparameter

Cannot be used after DDL operations

Recovery of PL/SQL package after

wrong compilation:SQL> SELECT text FROM dba_sourceAS OFTIMESTAMP TO_TIMESTAMP('11.04.200621:40', 'DD.MM.YYYY HH24:MI')

WHERE owner='APP_USER1' ANDNAME='LOST_PKG';

Agenda


55/100

55 of 100

g

Flash Recovery Area



Database Hangs


Conclusion

Flashback DATABASE

Flashback DROP

Flashback TABLE

Flashback QUERY



FLASHBACK VERSIONS QUERY


56/100

56 of 100

FLASHBACK VERSIONS QUERY

Audit Rows Changes

Retrieve all versions of the rows

between two points of time

Uses UNDO tablespace SQL> SELECT versions_xid, name FROM

my_tableVERSIONS BETWEEN TIMESTAMP

t1AND t2;

Very useful for auditing of user actions

Agenda


57/100

57 of 100

Flash Recovery Area



Database Hangs


Conclusion

Flashback DATABASE

Flashback DROP

Flashback TABLE

Flashback QUERY



FLASHBACK TRANSACTION QUERY


58/100

58 of 100

FLASHBACK TRANSACTION QUERY

Audit Transaction Changes

Displays which transaction were responsible for

certain changes for a given interval of time: SQL> SELECT start_scn, commit_scn,operation, logon_user,undo_sql FROMFLASHBACK_TRANSACTION_QUERY;

Uses UNDO tablespace Returns the exact undo statement to undo the

transaction

Cannot be used after DDL operation over thetable

Recovery with Flashback Features -


59/100

59 of 100

Recovery with Flashback Features -

Summary

Very powerful

Faster recovery

Faster response of human errors

Needs a space It is only an addition to your backup strategy,

not a replacement for it

There is no full protection from human errors- the DBA is a human too

Agenda


60/100

60 of 100

Agenda

Flash Recovery Area

Flashback Technology Enhancements


Physical Backup & RecoveryEnhancements

Conclusion



61/100

61 of 100


An UNDO tablespace with RETENTIONGUARANTEEcan cause the database to

HANG

A SYSTEM tablespace that cannotextend can cause the database to

HANG



62/100

62 of 100


The Database cannot HANG if the

FRA is Full Only two exceptions of the above:

1. Archived logs that are treated as

permanent files in FRA and spacepressure from ARC process

2. Flashback logs that are treated as

permanent files. Caused by GuaranteedRestore Points

Database Hangs - Recommendations


63/100

63 of 100

Database Hangs Recommendations

Set smaller and reasonable recovery window

Backup archived logs regularly

Configure at least two archivelog destinations

Give more physical space to FRA

Configure the FRA size to be at most 90% ofthe real physical available space

Delete guaranteed restore points as soon aspossible

Monitor FRA to ensure that there us no spacepressure

ARC Process & Database Hangs


64/100

64 of 100

ARC Process & Database Hangs

Not started ARC process after puttingthe database in ARCHIVELOG modecan cause a hang

ARC process is started automatically in10g after putting the database in

ARCHIVELOG mode

Agenda


65/100

65 of 100

Flash Recovery Area



Physical Backup &

Recovery Enhancements Conclusion

Incrementally UpdatedBackups

Change Tracking File

Compressed Backups

Simplified RESETLOGS

Preview and ValidateBackups

New RMAN Views

Easy Tablespace Transport

Oracle Secure Backup

Miscellaneous - RMAN

Recovery with Incrementally Updated


66/100

66 of 100

y y p

Backups

Incremental backups capture only blockchanges since the last backup

In 10g there is ability to recover by using

incrementally updated backup files

Incremental backups are applied to the

datafile image copies (level 0)

Incrementally Updated Backups


67/100

67 of 100




68/100

68 of 100

y p p

RMAN> RUN {

RECOVER COPY OF DATABASE WITH TAG

'incr_updated_baclup';

BACKUP INCREMENTAL LEVEL 1 FOR RECOVER OF COPYWITH TAG 'incr_updated_backup'

DATABASE;

}

Provides smaller Recovery Time Objective

In case of real recovery image copies will beupdated with last incremental backup plus

needed small amount of archived logs



69/100

69 of 100


In case of media recovery RMAN will

choose the incremental backups overthe available archived logs

Then only a small amount of archived

logs will be applied It is much faster approach

Ensures much faster media recovery

Oracle-Suggested Backup Strategy


70/100

70 of 100

Oracle Suggested Backup Strategy

RUN {

ALLOCATE CHANNEL oem_disk backup DEVICE TYPE DISK;

RECOVER COPY OF DATABASE WITH TAG ORA$OEM_LEVEL_0;BACKUP INCREMENTAL LEVEL 1 CUMULATIVE COPIES=1 FORRECOVER OF COPY WITH TAG ORA$OEM_LEVEL_0 DATABASE;

}

This strategy is for 1 day recovery window

only Shouldnt be used if there is configured

recovery window bigger than 1 day

Instead this use UNTIL TIME clause inRECOVER COPY statement

Oracle-Suggested Backup Strategy


71/100

71 of 100

Oracle Suggested Backup Strategy

Agenda


72/100

72 of 100

Flash Recovery Area



Physical Backup &




Compressed Backups


Preview and Validate

Backups

New RMAN Views


Oracle Secure Backup Miscellaneous - RMAN

Fast Incremental Backups with Change


73/100

73 of 100

Tracking File

Usually Incremental backups are slower

All blocks in a datafile are scanned This can result in bigger backup window

In 10g can be used a Change TrackingFile to perform faster incrementalbackups

Tracks the physical location of alldatabase changes



74/100

74 of 100

g g

RMAN uses it to find the location ofchanged blocks since the last

incremental backup Only these blocks will be scanned and

included in the backup

Improves significantly incrementalbackup strategies

Can make an incremental backup up to20 times faster



75/100

75 of 100

Change Tracking is disabled by default

Has minimal performance overhead

Enabling: SQL> ALTER DATABASE ENABLE BLOCKCHANGE TRACKING;

Uses the Database Area by default: DB_CREATE_FILE_DEST

The size of the Change Tracking File isaround 20 MB

Starwood Hotels Results


76/100

76 of 100

Oracle Open World 2005 - Session Id: 1181 Before

8 TB Data Warehouse

Backup takes 19 hours to complete Incremental backups have size 500 GB

Strategy

Incrementally updated backups Change Tacking File

After Backup takes 2 hours to complete

No need to perform full backup every Sunday Faster recovery

Fast Recovery with Disk-Based Strategy


77/100

77 of 100

Recovery strategy in case of media failure: Backup:

Incrementally updated backups in FRA Recovery

RMAN> SWITCH DATABASE TO COPY;

RMAN> RECOVER DATABASE;

Start the database by using its image copy,multiplexed control file and online redo logs fromFRA

Take backup immediately after the recoveryoperation

Agenda


78/100

78 of 100

Flash Recovery Area



Physical Backup &




Compressed Backups



Backups

New RMAN Views



Less Space for Backups with Compressed


79/100

79 of 100

Backups In 10g backups can be compressed with

RMAN

RMAN> BACKUPAS COMPRESSED BACKUPSETDATABASE;

Only for backupsets, not for image copies

1/5 of the size of the original files RMAN automatically uncompress during

recovery operations

The speed of backup & recovery operationsdepends on the CPU resources

Agenda


80/100

80 of 100

Flash Recovery Area



Physical Backup &




Compressed Backups



Backups

New RMAN Views



Simplified Recovery Through RESETLOGS


81/100

81 of 100

Before 10g - after every RESETLOGS a fullbackup must be performed immediately. Oldest

archived logs was not usable

In 10g there is ability to recover to an oldestincarnation. No need to perform full backup after

every RESETLOGS

The most important change is the new archivedlogs format:LOG_ARCHIVE_FORMAT="log%t_%s_%r.arc"

Simplified Recovery Through RESETLOGS


82/100

82 of 100

First archived log from Incarnation 17: ARC00001_0587681349.001

Last archived log from Incarnation 16: ARC00281_0587468099.001

Agenda


83/100

83 of 100

Flash Recovery Area



Physical Backup &




Compressed Backups



Backups New RMAN Views



Preview and Validate Backups


84/100

84 of 100

To preview backups and commands that willbe used in a subsequent restore operation: RMAN> RESTORE DATABASE PREVIEW;

RMAN> RESTORE ARCHIVELOG FROM TIME 'SYSDATE-7' PREVIEW;

To test backups in a hypothetical recovery

situation: RMAN> RESTORE CONTROLFILEVALIDATE;

RMAN> RESTORE DATABASEVALIDATE;

RMAN> RESTORE ARCHIVELOG FROM TIME 'SYSDATE-7'

VALIDATE; RMAN> RESTORE DATABASE ARCHIVELOG FROM TIME

'SYSDATE-7'VALIDATE;

Agenda


85/100

85 of 100

Flash Recovery Area



Physical Backup &




Compressed Backups






New Views for RMAN (10g R2)


86/100

86 of 100

V$RMAN_BACKUP_JOB_DETAILS

V$BACKUP_ARCHIVELOG_DETAILS

V$BACKUP_ARCHIVELOG_SUMMARY

V$BACKUP_CONTROLFILE_DETAILSV$BACKUP_CONTROLFILE_SUMMARY

V$BACKUP_COPY_DETAILS

V$BACKUP_COPY_SUMMARY

V$BACKUP_DATAFILE_DETAILSV$BACKUP_DATAFILES_SUMMARY

V$BACKUP_PIECE_DETAILS

V$BACKUP_SET_DETAILS

V$BACKUP_SET_SUMMARY

V$BACKUP_SPFILE_DETAILSV$BACKUP_SPFILE_SUMMARY

Agenda


87/100

87 of 100

Flash Recovery Area



Physical Backup &




Compressed Backups






Cross-Platform Transportable Tablespaces


88/100

88 of 100

Easily move tablespaces between LittleEndian and Big Endian OS platforms:

RMAN> CONVERT TABLESPACE USERS

TO PLATFORM'Solaris[tm] OE (32-bit)'DB_FILE_NAME_CONVERT

'E:\oracle\oradata\orcl102','E:\oracle\oradata\';

V$TRANSPORTABLE_PLATFORM

Agenda


89/100

89 of 100

Flash Recovery Area



Physical Backup &




Compressed Backups






Oracle Secure Backup (10g R2)


90/100

90 of 100

Media ManagementSoftware coming fromOracle

Centralized backupmanagement

Security policy based

Supports most of tapedevices

Encryption to tapes

Expected in May 2006

Agenda


91/100

91 of 100

Flash Recovery Area



Physical Backup &




Compressed Backups








92/100

92 of 100

(10g R2 EE) - Dynamic Channel Allocation overthe instances in RAC

(10g R2) - RMAN Channel Failover betweeninstances in RAC

(10g R2 EE) - RMAN encrypted backups RMAN> CONFIGURE ENCRYPTION ALGORITHM'algorithm_name';

Backup database to image copies: RMAN> BACKUPAS COPY DATABASE;



93/100

93 of 100

(10g R2) - Transportable TablespaceSets from Backups

Before 10g R2 tablespaces can betransported only if they are in read-onlymode during tablespace transport process

In 10g R2 there is capability tablespaces tobe transported from backups instead ofdata files

Can be very useful for OLTP systems



94/100

94 of 100

(10g R2) - RMAN excludes empty datablocks from backups. It can do this even

in MOUNT stage (10g R2) - Automatic Tempfile Creationafter Media Recovery with RMAN

Automatic Recovery of files that havenever been backed up: RMAN> RESTORE DATABASE;

Needs all archived redo logs from the timeof the data file creation till restore point



95/100

95 of 100

Drop the database with simple command: RMAN> DROP DATABASE;

RMAN> DROP DATABASE INCLUDING BACKUPS;

Cataloging whole directories with RMAN RMAN> CATALOG START WITHD:\my_backups;

Specifying Limits for Backup Duration: RMAN> BACKUP DATABASE DURATION 07:00;

RMAN> BACKUP DATABASE DURATION 07:00MINIMUM LOAD|TIME;



96/100

96 of 100

Cross-Platform Transportable Databases

A Whole Database can be transferredbetween different OS platforms

RMAN command: CONVERT DATABASE

Restriction: Target and Destination Platformmust be with same endian format

User-Managed Backups


97/100

97 of 100

In 10g the whole database can be put inOnline Backup Mode: SQL> ALTER DATABASE BEGIN BACKUP;

SQL> ALTER DATABASE END BACKUP;

Conclusion


98/100

98 of 100

Unified Storage for a Disk-Based

Backup Strategy Fast recovery from Human Errors with

Powerful Flashback Features

Faster Physical Backups

Faster Recovery from Media Failures

Integration with Enterprise Manager


99/100

99 of 100

A Backup is only as good asthe Recovery it can provide

Questions & Answers


100/100

100 of 100

Questions & Answers

URL: http://dba-blog.blogspot.com

Email: [email protected]

backup&recovery.enhancements.in.oracle10g-presentation.pdf

Documents